Biological nitrogen fixation is a key driver of global primary production and climate. Decades of effort have repeatedly updated nitrogen fixation estimates for terrestrial and open ocean systems, yet other aquatic systems in between have largely been ignored. Here we present an evaluation of nitrogen fixation for inland and coastal waters. We demonstrate that water column and sediment nitrogen fixation is ubiquitous across these diverse aquatic habitats, with rates ranging six orders of magnitude. We conservatively estimate that, despite accounting for less than 10% of the global surface area, inland and coastal aquatic systems fix 40 (30 to 54) teragrams of nitrogen per year, equivalent to 15% of the nitrogen fixed on land and in the open ocean. Inland systems contribute more than half of this biological nitrogen fixation.

• MeSH
• dusík metabolismus   MeSH
• ekosystém * MeSH
• fixace dusíku * MeSH
• geologické sedimenty chemie   mikrobiologie   MeSH
• mořská voda * mikrobiologie   chemie   MeSH
• oceány a moře MeSH
• Publikační typ
• časopisecké články MeSH
• Geografické názvy
• oceány a moře MeSH
• Názvy látek
• dusík MeSH

Tidal marshes store large amounts of organic carbon in their soils. Field data quantifying soil organic carbon (SOC) stocks provide an important resource for researchers, natural resource managers, and policy-makers working towards the protection, restoration, and valuation of these ecosystems. We collated a global dataset of tidal marsh soil organic carbon (MarSOC) from 99 studies that includes location, soil depth, site name, dry bulk density, SOC, and/or soil organic matter (SOM). The MarSOC dataset includes 17,454 data points from 2,329 unique locations, and 29 countries. We generated a general transfer function for the conversion of SOM to SOC. Using this data we estimated a median (± median absolute deviation) value of 79.2 ± 38.1 Mg SOC ha-1 in the top 30 cm and 231 ± 134 Mg SOC ha-1 in the top 1 m of tidal marsh soils globally. This data can serve as a basis for future work, and may contribute to incorporation of tidal marsh ecosystems into climate change mitigation and adaptation strategies and policies.

• Publikační typ
• časopisecké články MeSH
• dataset MeSH